Method of assembling terminal connectors



Dec. 13, 1960 R. A. CHADWICK 2,963,775

METHOD OF ASSEMBLING TERMINAL CONNECTORS Filed June 24, 1959 I INVENTOR.fleas/e7 AL 7/ (WAD/476K METHOD OF ASSEMBLING TERMINAL CONNECTORS RobertAlvin Chadwick, La Mesa, Califi, assignor to The Thomas & Betts C0.,Elizabeth, NJ., a corporation of New Jersey Filed June 24, 1959, Set.No. 822,529

1 Claim. (Cl. 29-15555) This application is a continuation in part of mycopending application Serial No. 324,359, filed December 5, 1952, nowabandoned.

The invention relates to insulated electrical terminal connectors of thecharacter disclosed, for example, in Patent 2,769,965, issued to JohnNelson Frey on Novemher 6, 1956, and more particularly to a linearassembly of a plurality of such terminal connectors wherein theinsulating sleeves thereof are integrally connected in parallel, spacedrelation.

More specifically, the invention resides in a linear assembly of aplurality of equally spaced, individually complete insulated terminalconnectors in flexible strip form and of a size adapted for use with 22to 18 wire size conductors, for example, wherein the terminal connectorsare interconnected by a narrow web of plastic insulating materialintegrally connecting each adjacent pair of the insulating sleevesthereof at diametrically opposite points on one peripheral edge thereof.

Similar prior art terminal connectors, as utilized separatelyheretofore, involved certain disadvantages in that in the attachment ofone of such terminal connectors to a wire conductor requiredconsiderable time by reason of the small size thereof and the difficultyin manipulating the same during such operation, more especially when aplurality of such connectors had to be secured one to each conductor endportion in a large bundle thereof,

as in an ignition or other electric circuit harness utilized in largeaircraft assemblies, for example. Moreover, the feeding of suchindividual terminal connectors from a hopper charged with a large numberthereof involved complicated apparatus in which the feed thereof fromthe hopper and from station to station, was not practical and/orefiicient by reason of the configuration of the terminal connectors.

Non-insulated terminal connectors are also known which are produced instrip form, with the connectors disposed in end-to-end tandem relation,for feeding to a crimping and severing apparatus, as disclosed in Patent2,494,137, issued January 10, 1950', to R. Martines. Strips of suchinterconnected terminal connectors are usually cadmium-plated or tinned,after the production thereof, to preclude corrosion. Thus, such terminalconnectors are also objectionable by reason of the fact that, in thesevering of each terminal connector from the strip, the plated or tinnedcoating is mutilated at the points of severance thereon, whereby theconnectors are rendered subject to corrosion.

Accordingly, it is an object of the invention to provide a linearassembly of equally spaced, insulated terminal connectors in flexiblestrip form which may be handled manually, fed to an automatic crimpingand severing mechanism or convoluted in coil formation for future saleor use.

Another object of the invention is to provide a linear assembly ofindividually complete, insulated terminal connectors in flexible stripform, whereby a non-cornited States Patent rosive metallic coatingplated on the conductive elements thereof is not mutilated in thesevering of each individual terminal from the strip.

A further object of the invention is to provide a plurality ofopen-ended insulating sleeves in a form in which the insulating sleevescan be handled manually as a group and successively separated duringsuch handling thereof.

Another object of the invention is to provide a plurality of open-endedinsulating sleeves as interconnected, equally spaced elements of aone-piece molded plastic strip adapted to be fed to a suitable machinefor successively inserting and securing conductive elements therein toform individually complete insulated terminal connectors, successivelyinserting and securing a wire conductor in each terminal connector, andsuccessively severing each terminal connector from the strip.

A further object of the invention is to provide a linear assembly ofinterconnected, insulating sleeves in the form of a molded, flexibleplastic strip wherein the opposite free ends of each strip are providedwith complementary ball-and-socket-forming connections, whereby aplurality of such strips may be detachably connected in end to endrelation.

With the above and other objects in view, the invention resides in thenovel construction, combination and arrangement of parts, the novelfeatures of which are set forth with particularity in the appendedclaim, the invention itself, however, both as to its organization andmethod of assembly, together with additional objects and advantagesthereof, being best understood from the following description of aspecific embodiment thereof, when taken in connection with theaccompanying drawings, in which:

Figv 1 is a fragmentary view of a molded plastic grid in plan andcomprising a series of equally spaced, interconnected, open-endedinsulating sleeves illustrating the manner in which a plurality oflinear strips of such insulating sleeves are produced;

Fig. 2 is a fragmentary plan view of a strip of insulating sleeves assevered from a molded grid thereof shown in Fig. 1, and illustrating anew article of manufacture in accordance with the invention;

Fig. 3 is a sectional view taken on the line 33 of Figure 2, showing oneof the molded insulating sleeves in axial section;

Fig. 4 is a fragmentary sectional View of a strip of interconnectedinsulating sleeves illustrating the successive insertion into eachinsulating sleeve in the strip of each of a pair of conductive sleeveelements, and the securing of one of said sleeve elements within theother of said elements;

Fig. 5 is a schematic view illustrating the manner in which a strip ofinsulated terminal connectors, as assembled in Fig. 4, may be fedstep-by-step in a crimping and severing apparatus to crimp each terminalconnector on the stripped end portion of an insulated wire conductor,through its insulating sleeve, and sever the connecting plastic webtherefrom while severing each insulated terminal connector from thestrip;

Fig. 6 is a plan view of an insulated terminal connector as completed,either manually or in automatic feed mechanism in accordance with theinvention;

Fig. 7 is a sectional view of the completed terminal connector taken onthe line 7-7 of Fig. 6; and

Fig. 8 is a perspective view of a portion of a linear as sembly ofinterconnected insulated terminal connectors showing a preferred form ofthe invention wherein the connecting webs between each pair of theinsulating sleeves are of uniform cross-section throughout with thelargest transverse dimension thereof disposed in parallelism with theaxes of the connected insulating sleeves.

Referring to the drawing, Fig. 1 is intended to exemplify, in plan, arectangular grid 10, molded of a synthetic polymeric amide, commonlyknown as nylon, and comprising a plurality of parallel rows of equallyspaced, open-ended sleeves 12, each having a common wall thickness andopposite end portions of different internal and external diametersforming an inclined annular shoulder 14 therebetween mid-way of thelength thereof, as in Fig. 3, the axes of the sleeves 12 being disposedin equally spaced, parallel relation with fiat integral webs 16 disposednormal thereto and connecting each adjacent pair of the sleeves 12 atdiametrically opposite points on the largest peripheral edge 18 of eachsleeve.

The molded grid 10, exemplified in Fig. 1, is formed in a sizesufiicient to provide forty-eight sleeves, for example, twenty four oneach side of the medial line ab, and the parallel columns of sleevessubsequently severed therefrom at a plurality of points, generallyindicated at 20, to provide flexible strips 22 of the molded sleeve 12,as exemplified in Fig. 2. Preferably, although not necessarily, the gridin Fig. 1 may include a free end web portion 16b, integral with the lastsleeve 12 at each end of each column or row thereof, definingcomplementary ball-and-socket connecting means 24, or the like, forexample, whereby a plurality of strips 22 may be detachably connected inend-to-end relation for a purpose hereinafter described.

Further in accordance with the invention and as best shown in Fig. 4,each insulating sleeve 12 in a strip 22 thereof is subsequently providedsuccessively, either manually or by means of an automatic intermittentfeed mechanism, with a frictionally fitted liner sleeve 26 of thinconductive metal having a corresponding inclined, annular shoulder 28,intermediate its ends, and a length slightly less than the length of theinsulating sleeves 12. Thereafter, the wire barrel portion 30, of anapertured tongue 32, having its free annular end internally chamfered asat 34, is inserted in the smallest end opening of the liner sleeve as,previously fitted in an insulating sleeve 12, whereupon the intrudedchamfered end of the wire barrel 3!? is flared outwardly against theinclined shoulder 28 of the liner sleeve 26, as by means of a suitableupsetting punch, as exemplified at 36, whereby the wire barrel 30 issecured within the thin liner sleeve 26 and the liner sleeve within itscorrelated plastic sleeve 12, against relative movement.

It is to be observed that the web 16 connecting each adjacent pair ofinsulating sleeves 12 in a strip 22 thereof is preferably formed withits dimension of greatest width disposed in parallelism with the axes ofthe sleeves 12, whereby to facilitate convoluting such strips into coilform if desired.

Further in accordance with the invention and as shown in Fig. 5, acombined web severing and wire barrel crimping tool A includes an anvilB provided with a fixed jaw C and a relatively movable jaw D, with theparts so related that, with an insulated terminal connector 38, in astrip 22 thereof, located therebetween and the stripped end of aninsulated wire conductor 40, intruded into its wire barrel portion 3%squeeze pressure may be subsequently applied thereon through itsinsulating sleeve 12, to deform one end of its liner sleeve 26 intocrimped engagement with the insulation covering adjacent the intrudedstripped end portion of the wire conductor 40, and squeeze pressureapplied, at the same time, through the opposite end portion of theinsulating sleeve 12, and its liner sleeve 26, to deform the wire barrelportion 30 into crimped engagement with the stripped end portion of theinsulated wire conductor 40, intruded therein, as more fully disclosedin the herein-identified Frey patent.

Further in accordance with the invention, the movable jaw D of the toolA, includes an integral extension E, projecting therefrom in a directionlengthwise of the strip .22 of insulated terminal connectors 38, forsevering the webs '16, one after the other from the strip 22. The

lower edge of the aforesaid extension E is of inverted W-configurationto provide two knife-like cutting edges F and G, spaced apart a distanceexactly equal to the length of the web 16 between each adjacent pair ofinsulated terminal connectors 38 in the strip thereof. The left cuttingedge F is spaced from a stop wall H of the tool A, a distance equal tothe largest outer diameter of the insulating sleeves 12 of the terminalconnectors 38. The cutting edges F and G, as aforesaid, have a width,considered transversely of the drawing sheet, greater than the width ofthe opposite ends of the web 16 tobe severed from each adjacent pair ofthe insulating sleeves 12, and, in genera-l, it is the intent to severthe webs 16, close to the periphery of the sleeves 12, to substantiallypreclude residual burrs or like projections thereon.

In the schematic arrangement shown in Fig. 5 it is intended, upon eachactuation of the tool A, that each successively advanced insulatedterminal connector 38 will be crimped and severed from the balance ofthe strip, after the insertion of the stripped end portion of aninsulated wire conductor 40 therein, and that some suitablestrip-feeding device, such as a star-wheel or a spring loaded pusher P,for example, may be utilized to advance each strip 22 of connectors 38with a step-by-step action to bring the next connector in the stripagainst the stop wall H and into position to be crimped and then severedtherefrom.

Further in accordance with the invention and as illustrated in Fig. 8, amolded strip 22 of insulating sleeves 12, as above described, may alsobe formed in a mold adapted for the production of a plurality ofseparate individually complete strips 22 of insulating sleeves, with orwithout a complementary connecting means at the respective ends thereof,wherein the webs 16, integrally connecting the larger open ends of eachadjacent pair of the insulating sleeves 12 at diametrically oppositepoints on the peripheral edge thereof, have a uniform cross section ofsmall area throughout their entire length and with the largesttransverse dimension of the connecting webs 16 disposed in parallelismwith the axes of the insulating sleeves 12.

As previously described, the insulating sleeves 12 are each providedwith a thin liner sleeve 26 of ductile metal and a wire barrel 30 ofductile metal, including an apertured tongue 32 extending from thesmaller end of the liner sleeve, the strips 22 being marketed as shownand adapted to be fed to a crimping and severing mechanism or eachinsulated terminal connector 38 manually severed from a strip 22thereof, as needed. Thus, by means of a linear assembly of insulatedterminal connectors in flexible strip form, it is possible to manipulatesuch connectors more readily, especially when it is realized theconnectors are usually of such small size as to be difiicult to holdbetween the fingers. Moreover, in strip form, the insulating sleeves canbe more readily equipped with the conductive metal elements than is thecase when separate sleeves must be handled to insert such elementstherein to produce the insulated terminal connectors, as described.

Inasmuch as the insulating sleeves 12 are identical, one with the other,and all exactly and equidistantly spaced apart, each sleeve will occupythe same position as every other sleeve when brought into position to beoperated upon in a crimping and/or severing apparatus.

While the invention has been illustrated and described with respect to apreferred embodiment thereof, it is to be expressly understood thatvarious changes and modifications may be made therein without departingfrom the inventive concept underlying the same. Therefore, the inventionis not to be limited except as is necessitated by the prior art and thescope of the appended claim.

What is claimed is:

In the art of assembling terminal connectors of the type comprising aplastic insulating sleeve and a pair of relatively short tubular metalmembers secured therein in telescopic relation wherein the inner tubularmember comprises an apertured tongue and a wire barrel coextensivetherewith having its free annular end internally chamfered, the methodwhich consists in molding a plurality of open-ended insulating sleevesin flexible strip form, each sleeve having a common wall thickness andopposite end portions of different internal and external diametersforming an inclined annular shoulder therebetween, the axes of saidinsulating sleeves being disposed in parallel, spaced-apart relationwith integral webs disposed normal thereto and connecting each adjacentpair of insulating sleeves at diametrically opposite points on thelargest peripheral edge of each sleeve, inserting a complementary thinmetal liner sleeve successively within each insulating sleeve, insertingthe chamfered free end of the wire barrel portion of an apertured tonguesuccessively into the smallest diametered end of the liner sleeve ineach insulating sleeve, upsetting the chamfered end of each wire barrelportion successively against the inclined shoulder of the metal linerwithin each insulating sleeve, inserting a stripped end of an insulatedconductor successively into the wire barrel within each insulatingsleeve, successively subjecting each wire barrel to a crimping operationtransversely thereof through its correlated insulating sleeve, andsuccessively severing each insulating sleeve from the strip thereof.

References Cited in the file of this patent UNITED STATES PATENTS Re.23,688 Watts July 21, 1953 2,569,083 Wilhelm Sept. 25, 1951 2,610,390Locke Sept. 16, 1952

